The authors of the bipartisan plan said Wednesday they'll push the proposal forward, even as President Donald Trump's stance ricocheted from supportive to disdainful to arm's-length and the plan's fate teetered.

"If something can happen, that's fine," Trump told reporters at the White House. "But I won't do anything to enrich the insurance companies because right now the insurance companies are being enriched. They've been enriched by Obamacare like nothing anybody has ever seen before."

The agreement by Sens. Lamar Alexander, R-Tenn., and Patty Murray, D-Wash., on a two-year extension of federal subsidies to insurers that Trump has blocked gained an important new foe. The anti-abortion National Right to Life said it opposed the measure because it lacked language barring people from using their federally subsidized coverage to buy policies covering abortion, said Jennifer Popik, the group's top lobbyist.

In another blow, Doug Andres, spokesman for House Speaker Paul Ryan, R-Wis., said Ryan "does not see anything that changes his view that the Senate should keep its focus on repeal and replace of Obamacare." With hard-right conservatives wielding considerable influence and unwilling to prop up President Barack Obama's health care law, it was unclear if Ryan would be willing to even bring the measure to his chamber's floor.

Overall, it was a bad day for the bipartisan accord, with several Republicans conceding that it likely needed Trump's backing to survive.

"Without the president supporting it, I don't think you have the votes in the House or the Senate," No. 3 Senate GOP leader John Thune of South Dakota told reporters, adding, "We're stalled out."

Alexander and Murray shook hands on their agreement this week after months of intermittent talks. Failure to restore the federal payments to insurers could result in higher premiums for millions buying their own individual policies and drive carriers from unprofitable markets. Many in Congress would love to avoid blame for two such tumultuous events.

The compromise has won warm endorsements from Democrats and some Republicans. It includes steps won by Republicans to make it easier for insurers to avoid some coverage requirements under Obama's 2010 overhaul.

But Trump has lambasted the subsidies as insurance company bailouts.

"It's not a full approach and we need something to go a little further," said White House spokeswoman Sarah Huckabee Sanders.

The money reimburses carriers for lowering co-payments and deductibles for about 6 million lower-income customers, which the companies must do under Obama's statute.

Without those funds, insurers would likely boost premiums by an average 20 percent, the nonpartisan Congressional Budget Office has projected. This would especially hit many buying their own health insurance who make too much to qualify for tax credits that help reduce premiums for lower earners.

Confusingly, Trump praised the bipartisan agreement early Tuesday as a "very good solution," only to berate it in an evening speech. Some said his objections Wednesday to enriching insurers could be addressed by strengthening language in the compromise to ensure the money directly benefits customers, not companies.

"We will keep working on it," said Alexander. He said he and Murray would formally unveil the bill Thursday and predicted that "some form of the proposal" would become law by year's end. It could become part of a must-pass bill preventing a federal shutdown due in December.

"The president has had six positions on our bill," Murray told reporters. Asked if the measure was still alive, she said, "Of course it is."

Alexander said Trump called him Wednesday morning and encouraged him to continue his effort, but left wiggle room.

"I may want to add something to it," Alexander said in a brief interview with The Associated Press, describing what Trump told him about the deal. "And it may have to be part of a larger negotiation."

Senate Finance Committee Chairman Orrin Hatch, R-Utah, criticized the plan, saying: "It would last two years and spend a whopping amount of money and not solve the problem and lead us down a path of never getting the problem done." Senate Majority Leader Mitch McConnell, R-Ky., has been non-committal.

Senate Minority Leader Chuck Schumer, D-N.Y., said to address Trump's aversion to enriching insurers, Democrats had offered to delay the measure's impact for a month after enactment to let insurers lower premiums after payments were restored. Insurers in some states have installed higher premiums for next year, anticipating the subsidies would end. Schumer said White House officials rejected that idea.

GOP co-sponsors include Sens. John McCain of Arizona, Lisa Murkowski of Alaska and Tennessee's Bob Corker. Sen. Mike Rounds, R-S.D., said Alexander has eight or nine Republican co-sponsors, and Democrats plan to provide an equal number to build bipartisan pressure.

Also behind the measure were America's Health Insurance Plans, the giant trade group for insurers; AARP representing the elderly; the National Retail Federation, which lobbies for merchants plus doctors, hospitals and patients groups.